Attics have been insulated to a higher degree over the past several decades, largely due to rising energy costs and heightened awareness of the loss of heated air through the ceiling between living space and attic space. Such attic insulation may be significant in reducing overall heating costs. A substantial amount of energy can be lost from the living spaces of residences to the attic space, above the living space. Generally, the heated air rises, and through either actual air flow or heat transfer, heat escapes from the living space. Where attics are significantly insulated, heat is still transferred through the thin layers which normally provide a barrier between the attic and living space in a region of attic stairs or attic openings. Traditional arrangements even unintentionally allow for air flow through cracks between an attic stair door and a region which defines the attic opening.
Attic insulation covers have been proposed in the past which provide significant barriers as to heat loss through the attic opening space. U.S. Pat. No. 4,550,534 to Mariano et al. discloses a ceiling cover for an attic floor well opening and attic stairs. This cover consists of a dome made of insulated material. Such a dome is basically a single integral unit. This provides significant benefits with regard to preventing heat transfer or preventing heated air flow from the living space to the attic. However, this preformed device can be quite awkward with regard to installation and particularly storage and shipping. As the device is a single piece and cannot be disassembled, a large container is required for shipping the unit. Further, the large size can be quite problematic with regard to installing the cover and moving it through the house. Also the large size requires significant cost in creating the mold, and a separate mold is required for each size opening.
U.S. Pat. No. 4,658,555 discloses an attic hatchway insulating cover which is made of a solid piece of insulation such as cellular foam, having a high thermal "R" value. This foam is rigid and is lightweight. A thin covering can be provided over the foam to protect it from being damaged. Although this structure is less prone to damage as compared to the ceiling cover proposed by Mariano et al., this structure nevertheless still has the problems of Mariano including the problem of the device requiring a large device for shipping and the hatchway being problematic with regard to installation.
U.S. Pat. No. 5,274,966 discloses an insulating cover for attic stair opening which is formed of two pieces made of a strong lightweight insulating material such as polyurethane. The two pieces or two sections combine together to form a single cover. These blow molded elements are still quite large in size and although the structure provides advantages by mounting by hinges, the structure is still quite large and requires large boxes for shipping. It also has the same mold requirements as Mariano.
U.S. Pat. No. 4,832,153 discloses an attic stair insulating cover which is formed of several rigid foam or fiberglass elements. These plurality of pieces are fitted together into an operational position to form the cover. This arrangement provides some advantages with regard to shipping and assembly. However, the units are still quite large and for the most part cannot be provided in a flat state. Instead, large boxes are still required as the various elements still take up quite a bit of volume even in a disassembled state.
The U.S. Pat. No. 4,281,743 discloses an insulating enclosure for an attic stairway. The arrangement includes a plurality of elements which combine to form the enclosure. The enclosure is formed of side members, a side wall and a top wall. A tiny groove connection arrangement is provided for connecting the various elements. Each of the side members, top panels and expansion panels is preferably fabricated from the relatively lightweight material such as polystyrene foam or the like which has good thermal insulating qualities. This structure still relies on L shaped side elements which do not lie flat and requires additional volume when the unassembled pieces are shipped. Further, by forming the structural elements out of polystyrene foam, the assembled device is structurally somewhat weak and potentially prone to damage.